Since you agree that you should have followed through with what you told your D, what if you had simply told your XW, "You're right. That was wrong of me and I will apologize to her and make it up to her"? And left it at that without getting into a back and forth about it?
As far as staying out all night...when you do that, even if she is not your W any longer, she is still there with the kids, so you are putting her in a position where she is the sole caretaker without discussing it and agreeing in advance.
Don't think of it as answering to her. Think of it as independently taking responsibility for the kids.
I certainly don't know everything but with all of the ups and downs, one minute you're engaging in physical intimacy but without a clear agreement or commitment. I can't see how that helps either of you or the kiddos.
